Loans and Allowance for Credit Losses - Loans modified in troubled debt restructurings (Details) $ in Thousands	12 Months Ended
Dec. 31, 2020 USD ($) contract	Dec. 31, 2019 USD ($) contract
Loans and Leases Receivable Disclosure [Line Items]
Number of loans - restructured accruing \| contract	7	7
Number of loans - restructured nonaccruing \| contract	3	2
Number of loans \| contract	10	9
Restructured accruing	$ 10,472	$ 16,578
Restructured nonaccruing	8,712	2,512
Troubled Debt Restructured	19,184	19,090
Specific allowance	3,722	1,000
Restructured and subsequently defaulted	8,712	9,485
Commercial
Loans and Leases Receivable Disclosure [Line Items]
Restructured accruing	1,276	885
Restructured nonaccruing	0	142
Troubled Debt Restructured	1,276	1,027
Specific allowance	733
Restructured and subsequently defaulted		0
Income producing - commercial real estate
Loans and Leases Receivable Disclosure [Line Items]
Restructured accruing	9,183	14,806
Restructured nonaccruing	6,342
Troubled Debt Restructured	15,525	14,806
Specific allowance	2,989	1,000
Restructured and subsequently defaulted	6,342	7,115
Owner occupied - commercial real estate
Loans and Leases Receivable Disclosure [Line Items]
Restructured accruing	13	887
Restructured nonaccruing	2,370	2,370
Troubled Debt Restructured	2,383	3,257
Restructured and subsequently defaulted	$ 2,370	$ 2,370

Number of financing receivables outstanding that have been modified by troubled debt restructurings.

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Post-modification amount of investment in financing receivables modified by troubled debt restructurings accruing.

+ References

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Post-modification amount of investment in financing receivables modified by troubled debt restructurings nonaccruing.

+ References

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Number of accruing financing receivables that have been modified by troubled debt restructurings.

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Number of nonaccruing financing receivables that have been modified by troubled debt restructurings.

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- Definition

Amount of credit loss expense (reversal of expense) for financing receivable from change in methodology.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 11
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919244-210447

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- Definition

Amount, after troubled debt restructuring, of modified financing receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524

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- Definition

Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953682-111524

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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